HUE035572T2 - Method for casting a cast part - Google Patents

Description

METHOD FOR CASTING A CAST PART

Description [0001] The invention relates to a method for casting a oast part according to the tilt casting principle ns ontanod in the preamble of clair; 1, (0002] A oat hod of trie typo manó ionod in the introduction is also di no lot ad in ub102707623681ΑΊ . (0003] A mosnod for tilt casting it described in 002010/01806811. kith the known method, the precess of recasting is initiated by tilting the peering flask. The pouring flask and/or the level of the molt in the pouring flask here is/are higher than the mode, so that the melt enfers the pouring flask with a relatively high kinetic energy. With the known approach, as is customary with such met beds, the melt is scooped cut of a Paie'" cut furnace using a ladle and then transferred from the ladle tó the peuring flask, which is then used to fill the mold. Additional casting methods arc doser rued in 03261.2 / 32 64 2 4 AÍ, 011020060.36112/11, hO2610/668116Λ1, OS 6,701,413 A as well as Ph1164273. (0004] One oisadrentage of the known methods is, among ether things, that eddies develop in the melt, and the moral oxide skin and the metal molt become mixed, which can therefore result in extremely negative effects on the bast structure of the resrsiting cast part as a result Of filling the pouring flask using the ladle. (0005] There fere one object of the present invention is to create a novel tilt casting method which will not have the disadvantages dafined above.

[0008] This object: is achieved with a method of the type defined in the introduction according to the i. nventuon by the features of the oharactericing part of ciaim 1.

[0007] A partiduidrly homogenous and 1ow-tarbuicace one ting process can he imp I enen ted when ne ing the approach: according te the invention. This nahes it possible to prevont itregular 11res in the structure of the material of ihe: oast piece. In particular by preventing recasting of the melt from the indie to the pouring flask, it is possible to achieve scooping and transport of the noir to the mold with an especially low incidence of eddies, since the net ai inéit is already agitated before transferring the melt from the posting flask to the mold, the melt can he posted, into the mold in a very uniform menner without eddies. Recasting here takes place at each a rate that the metal onide shin floats on the metal melt until the end of the recasting. This therefere ensures uniform casting of the metal melt in the mold, [0008] A pa circulariy ice-1 urbu'ier: ce recasting method can be achieved due to the fact that at least 801 of the metal oxide skin floats on the surface of the metal melt, [0009] it has proven to he especially advantageous if the metal crude skin remains in the pouring flask until reaching the final position. It is particularly favorable here if an area of the metal oxide skin facing away from the mold is the last to leave the nosring flask on reaching the final position and comes to lie at the surface of the metai melt in the mold, [0010] More than 80%, proie rabi y more than 85%, of the metal oxide skin advantageousiy comes to lie In a subsequent solidification position, which follows the final position in the area of a feeder of the mold.

[ÖÖ113 One variant cf the invention with which a. particularly high quality of the cast piece car; be aohieved prooi dee that the recasting takes place at a speed suck that the restai orn.de skin retains elastic and nndartaged an t i 1 r e a eh i ng t h e f i n a 1 p o s It 1 on .

[0012] P art i onia r i y 1 et - tu r b u len ce r e c a s 1 i n g in a c ht. eved. by the tarer, that the surface of the cotai, oxide skin in the pouring flask is enlarged during the recasting ef the beta! be it 1res:, the ponti ng flask into the no.r.sb This enoogirvent ensnres that the recasting of the notai melt takes place at an. optibura rate.

[ÖÖX3] .According to a preferred fe 1 inebent, which perfdtS a very accurate and defined recasting, it is provided that the pouring flask is connected to the bold before the reeastihg, and a relative position of the penning flask with respect to the bold is retained during: the recasting between the starting position and vne final position.

[00X4] Optional soi édification behavior of: the betal belt in the bold can he aohieved by the fact that the axis ef retatien in the starring position runs through the ns id, as seen from the penring flash, and either lies beneath the bold cavity or runs iron, the pouring flask behind the bold cavity or through the bold cavity or above the bold cavity. [9Ö1S] To prevent the cast piece: tree being dabaged due to the beta! oxide skin, it bay be provided according to a refi.nebent of the method according to the invention that the betal cxide skin fails into a feeder of the coif on reaching the final position or it slides into the sprue over the total width, [00:163 According to eno variant of the invention, which is character iced by a particularly calc, eddy-free pouring of the betel beit fron the pouring flask into the bold, it is possible to provide that the pouring flask is brought to the faeoc··' for the mole after scooping the metal ooit out of the hais-out furnace, wherein the pooring flash het a pouring zone, hy means of which the metal melt is poureo through the feeder inte the meld, toot that the contour of the peu ring tone conforms te the contour of a section of the feeder situated ih the startfug position at the bottom., as seen in the vertical direction, the pouring zone being connected directly and congraently te the feeder.

[Ö017J ft has proven to be pariiouiaf1y favorable if the contour of the feeder and the contour of the pouring zone are in a horizontal position in the starting position of are pivoted by an engin of at most 30° oat of the h o r i tout el position.

[0018] Very good resuits with regard te the guality of the cast piece can he achieved by the fact that, in the final position, the contour of the feeder and the contour of the pouring zone are rotated, by an angle of at roost 1/0'·' and at least bid with respect to the starling position.

[0019] It has proven to he e specie 1.1 y adventa geen s if, immediately after the end of the filling, the pouring flask is connected ho the metal melt within a period of et mest 5 seconds, in particular within a period of at most 3,5 seconds after the end of filling it with the metal melt, and if it is troughr into the starting position, due to the short docking time of the pouring fiask on the mold, an optimum casting temperature of the metal melt and Optimum flow behavior of same can he ensured. Optimum elastic properties of the metal oxide skin can also be achieved within the stated periods of time.

[0020] An optimum condition of the metal oxide skin and the moral melt for pouring can bo achieved by filling the pouring fiask with the metal melt in the hale-out furnace within a period of time amounting to at most 3.5 seconds.

[0021] Very good ros ólt o with regard to the structure oi the cost piece cop he acid eved by more the poor tog flock cod the mold frc.e the starting position to the final posit ion within a period of at post 8 seconds, in particular wither;, a period of at post t.o seconds.

[0022] is has proven to he particularly advantageous that the average temperature of the metal heit in the hate-oat furnace is at a letel onginat ing from a value range with a lower limit of 8«0::'C and an upper limit of ISO ha [ÖO233 in addition to the aforementioned period of time for scooping the metal melt, the metal melt can he scooped ooh of the halo-out furnace particularly smoothly and with little turbulence and a tow oxide content by the fact that the pouring flask has a slotted openihg in a regien facing away from the mold in the starting position, such that the pouring flask for scooping the metal melt eut of the bale-out furhade with the opening facing forward is immersed in the metal melt in the bale-out. farnape, [0024] According to another very advantageous variant of the invention, it is possible to provide teat the pouring flask and the mold are moved from the starting position into the final position in an excess pressura atmosphere, [ÖÖ253 According to an optimum embodiment with regard to productivity and the short process times, it may he advantageons te use at least three molds, arranged on a carousel, wherein the carousel rotates the three molds from a easting position, in which the menai melt is transferred from the porring flask to the mold, to a solidification position, in which the metal melt solidifies is. the mold, and then into an. operating position, in which the mold is opened and a cast part is removed from the mold, and thee the meld is ole aped, According to an advantageons refinement, two carousels may also he operated in parallel.

[0Ö2Ö] A very high productivity can be achieved with optimum quality of the cast pieces thereby produced due to the fact that the carouseX is rotated further in a cohstanf cycle having a value from a value range whose louer 1 trait is 10 seconds: and whose upper lifeit is 0 0 seconds, [ÖÖ27] Far a bur 1er under standing of the invention, if will now he explained in greater detail en the hasis of the loi loo rue figures:, [0028] the: figures shoe in greatly simplified schematic diagrams :

Figure 1 a pouring flask, a mold and a ba la-out furnace, such as those used In a method a co or di ng to the invent ion ;

Figure 2 a starting position of the pouring flask and the mold from Figure 1 before transferring a metal melt from the pouring flask to the: mold;

Figure 1 a final position ot the pouring flask and the mold from Figure z after trans fer ring the metal melt from the pouring flask to the mold;

Figure 4 a perspective view of the pouring flask and the mold from Figure 2;

Figtre 5 a section through the peering flask and the mold from Figure i;

Figure 6 a carousel with three molds, [0029] hccerdingly, it should be pointed out that, in the various embodiments described here, the same parts are labeled with th© same reference rumerals and/or the same composons designatdohs, wherein the disclosure content contained in the entire description ten logically alec be applied to the same parte having the sat- reference nttseraia and/or the tame oomponent designations,. The position specifieations need in the decoription, such as above, below, at the sice, etc., are hated Oh the tigere, as described and depicted directly, and these position statements are to be transferred accordingly to the new positron in the ease of a change in position.

[0030] The exemplary embodiments shew possible variants of the approach according to the invention, wherein it shosld be pointed cut here that the invention is not restricted to the specific variants of same illustrated hero, but instead varions combinai ions of the individual vari ant s with one another are: also possible, and these possible variations Pa síid on the teaching regarding the t e crude ai act ion are within the abilities of those skilled in the art in this technical field thanks to the present invention.

[0031] In. addition individual features or combinations of features of the different exemplary embed scents described, and illustrated here may else represent independent approaches according to the invention.

[0032] The object on which the independent approaches according to the .invention are based can be taken Írom the dose riot. ioni.

[0033] All the specif icatio.es regarding value ranges in the ' present description are to be understood to mean that ttese also include any and all subranges therefrom. For example, the notation .1 to 10 is to be understood to mean that all subranges starting from the lower limit of 1 and includf.ng the upper limit of 10, ire., all subranges, begin with a lower limit of 1 or more and end at an upper limit of lu er loss, for oxerpiu, 1 to 111 or 3,2 to 8,1 or 3,1 to 10 .

[0834] In part roti a r, the specific ended meat illustrated in Figure 6 nay fore the moot natter or an independent invention. The proviens and solutions adcofdlhg to the in vorn ion in this regard can be taten Iron the detailed de s o r ip t i οn s e f t hi s f ion r e, [0033] For the sake of order, it should be pointed ont in conclusion that, for a hotter understanding of the strnctnro of the oonpononts of the casting device esed to carry pet the rerhod, these corponenta have in arc cases been illustrated in enlarged and/or reduced forr and ate net drawn, to scale, [8836} According to Figuren 1 to 3, the casting in a netted aocording to the invention for casting a cast part is carried ont according to the lilt canting principle, in which a petal pelt 1 is recast free a tillable peering flask 2 into a no io 3 having a cold cavity 1 that replicates the cast part. An alupinnp alloy is especially preferably used as the petal pelt 1, e.g,, AC-AlSllOMgdCa}, Ad-AISi3Co3, AISilCul, Aid16Coi, The POid 3 is especially preferably a co id for high"stress a loei cur oorponents, such as cylinder heads of other ooppenenrs of rotor vehicle engines, for oxacpie.

[8837] In Figaros F-3, the pearssg flask 2 and the cold 3 are illustrated in different positions ever tire. The: recasting pay also fake place by roars of too or Pere poaring flasks 1, ehooh are arranged in parallel with one another and are also known as casting ladies. (0038] The peur ing flask 2 is advanced to the paid 3, preferahiy by a robot arp, and nonnented to the rend, for eraopie, by sospending it, after connecting the pouring flask 2 to the void 3, the robot arr can release the pouring flask 2 and is. the«, available for another operation,. the pouring flask 2 is preferably also filled with the heip of the robot arm, which 'Immerses the pouring flask 2 into the moral melt 1 of the Pale·’·out furnace r. The metal mehr hero is scooped directly out of the bale-Out furnace uslhg the pouring flask /.. During and/or immediately after the scooping, a metal oxide skin 1 forms: at the surfaee of the metal melt 1 la the pouring flask 2, The average romporaturo of the molten metal melt 6 in the Pale-out furrace a is at a revel originating from a value range, where the lower limit is Crif’C and the upper limit is ?80“C, {ÖÖ3SJ After filling the pouring flask 2, the metal melt 1 and the metal ex ide skin S flea ting on if are advanced to the mold 3. Then the metal meh. 1 is recast from She pouring flask 2 into the mold 3 by point rotation of the pouring flask 2 and the mold 3 about an axis of rotation a, out of a starting position and into a final nos if hum During the xerase las, most of the metal oxide skin C, at least 33% or even ail of the metal oxide skin floats on the metal melt 1 and remains essentially at the surface of the metal melt until reaching the final position, (0040] Äooording to one variant of the invention, the metal oxide skin 6 may also remain in the pouring flask 2 until reaching the final position, A region of the metal oxide skin t facing away from the mold 3 is the last to leave the pouring flask 2 on reaching the final position and cem.es to lie on the surface of the metal melt 1 ín the mold 3, here than 5 0%, preferably more than 95% of the metal oxide skin 3 is advantageously in the area of a feeder 7 of the mold 3 in a solidification position, which forlows the final positron chronologically, (0G4X} The he taf c.c skin t rehains elastic and nndahaged until reacting the final position. The surface of the xsetal oxide akin t ;..u the ponting flask 2 nay alee become larger during the transfer of the hetei he It X, in par Line's a n increasing in the direction of a pouring region of the pouring flask 2, Dao he the increase in surface area of the oserai oxide skin during the transfer,· a prr.lrf · up oalrt flow of the holten eet.al oxide in achieved.

[0042] The porul ng flask 2 is connected io the .cold 3 before the transfer begins, h relative petition of the pouring flask 2 with respect to the hole 3 is haintaineo ds.ee.ng the transfer here. the starting position and the final position, in ether cords, the penning flask 2 foiicws the hovehent of the hold 3 about the axis of rotatj.cn a. it has been found to be especially advantageous that fee axis of rotation a runs through the hold 1 in the starting position, wherein the uxia of rotation a. is either beneath the rsoid cavity 4 or behind the hold cavity i, as seen froh the pouring flask 2, or runs through the hold cavity 1 or is above the bold cavity 7, [0043] On the pouring end, the hold 3 hay have a feeder 7, In this ease, after scooping the hotai heir I out of the bale-out furnace S, the pouring flask 2 hay be advanced up to ire feeder 7 of the hold 3 and then connected to this feeder 7. The pouring flask 2 has a pouring tone 3, over whio.h the metal mount 1 floes into the feeder 7 and froh, there further into tun cold cavity 4. The contour of the penning zone 8 corne spends to the contour of a section of the feeder 7 lying at the bottom in the starting position, as seen rn the vertical direction, The pouring rone 8 is preferably connected directly and eongrnentiy to the feeder 7, The term "contoor7' as used in the present context is understood primarily to refer to the shape of a botton region and the adjacent outside edges and outside surfaces of the feeder 7 and the genreng tone 3 of the porring flask 2> (0044] After reaching the final position,; the natal oxide chin u drops onto the feeder 7 of the mold 3 or slides into the feeder 7.. The metal oxide skin preferably essentially slides into the feeder 7 oner the entire width thereof. [0045] According to figure 4f the posting flask 2 nay have a slotted opening 9 in a region facing away fror the mold 2: in the starting position, tor scooping the metál melt h out of the bale-cut farnaoe o? the posting flack i is immersed with the opening 9 at the front · nto the metal melt € in the baie-ont furnace 5, The slotted opening which stands vertically in the notai pelt. I of the taie-oat furnace 1 during the scooping operation, it is possible to macro that only clean oxide-free Petal wi 11 flew into the pouring flask 2 during the scooping operation. The pouring flask 2 is filled with the metal melt 6 in ins bale-out furnace ·> within a period of time, whose maximum durst ion is 3.5 seconds . (0046] Immediately after conclusion of the filling with the metal melt 1, the pouring flask 2 is connected to the mold 3 within h period of at most 5 seconds,· in particular within a period of at. most 3.1 seconds, and brought into the st ar t ing cos1t1on. (0047] As can be seen from Figure 5, in the starting position,· the contour of the feeder 7 end the contour of the pouring cone u ate in a nor 1 rental posirion. it should be pointed out that the corn.ours of the feeder 7 and of the pouring sone in the starting position can be pivoted about an axis of rotation a, up to an angle of at most 30 cut of the bori routai position, in the final pocitiorp the contour of the feeder 7 and the contour of the pouring sene 5 ere rotated by an angle of at moat 120° and at leant 60s witn respect to tue starting position. The pouring flask 2 and the mold 3 are moved eat of the starting position and into the final position within a period of at most 8 seconds, in particular within a peried or at most f.d seconds, [0048] it should also be pointed out here that the entire method according to the invention or even just the step of recasting of the natal melt I out of the pouring flask 2 and into the mold 3 oat he carried oat in an excess pressere atmosphere. To create the excess grossere, the peering flask 2 and the mold 3 may be arranged in a closed space, whioh can fee fid. led with a gas or a gas mist are, for example, an inert ter oboe tiro gas, rest It ing in an excess pressure with respect to the ambient atmosphere oarside of the room. Basically, the bate·· out furnace h could also be arranged in this room.

[0049] The omhodiment illustrated in figure 6 has at least three molds IC, II, 12, which are arranged on a carousel. This embodiment constitutes an independent embodiment per so, which may also bo used with casting methods ether than the one described above. The carousel rotates the three molds 10, 11, 12 around a easting position 1, in which the metal melt h is recast from the pouring flask 2 into the mold 10, II, 12 in a solrdifrontion position 11, in which the metal melt 1 solidifies in the mold 10, 11, 12 and then Into an operating position III, in which the mold 13, 11, 12 is opened and a east part is remevod from the mold 12, 11, 12, and then the mold 10, 11, 12 is cleaned. The carousel is rotated further in a constant cycle, which has a value originating from a value range whose lower limit is 70 seconds and whose upper limit is 30 seconds. In a preferred embodiment, this cycle amounts to 75 seconds and is obtained as follows: docking of the pouring flask 2 on the meld 11 takes J. S seconds in the casting position f, while tilting the pouring flask 2 and the mord 11 iron the starting position into the final posit loo takes 6.5 seconds. Piter reaching the final position, the pouring flask Is undocked troc the cold and is then available for a renewed scooping operatic·!, after another 56 seconds, the metal melt solidifies in the casting position 1, her further rotation of the held 11 into position IT, 9 seconds are required.

[0ÖSOJ In the solidification position 11, the metal melt I nno/or the oast pert solidify in the meld 10 for another 60 seconds, again requiring 9 seoonds for further retain.or· into operating position ill. In the operating position, the Cast part solidifies for 10 seconds more, then 9 seconds are required for opening the mo id, and 6 seconds are required for the robot to remove the cast part. Cleaning of the mold 3 takes 20 seconds^ and insertion of new sand cores takes 10 seconds. Then 9 seconds are required for closing the mold 3 and further rotating it into the easting posit ion 1. This yields a cycle time of 7 5 secends for further rotation from one of pool fions I, II, III into the n or t pc s i t1 on .

List of R<oi'erene© Nœerâis [0051] 1 metal τη© 1t 2 pouring flask 3 tölti 4 mo io os. vit y 5 baie-out furnace 6 met.o.1 oxide skit 7 foodor 8 pouring zout 9 ope .ping 10 mold 11 mord le mold Ä axis of ott. t: 1 pouring position il soildifiostiot position 1i 1 ope ra t i n g ρ os i t i οn

Claims (12)

Procedure for Casting Molding Patent Claims A method of casting castings using a tilting casting method, wherein the mold (3) is molded into a mold (3) with mold cavity (4) of at least one tiltable melt container (2), which is molded (1) directly into the molding container (2) directly immersed in the mold (3). immersed in the furnace (5), a metal oxide film (6) is formed on the surface of the metal melt (1) in the melt container (2), and a melt container (2) containing the molten core (1) and the metal oxide film (6) thereon is molded onto the mold (3). ) and displacing the sanitary napkin (1) from the melt tank (2) into the mold (3) by abrasion of the melt container (2) and the mold (3) into an end position around the axis of rotation (a), characterized by: how it is. melt container (2) includes a slit-like opening (S) in the initial position opposite to the Mold (3), and immersing the molten container (8) from the dipping oven (5) in the melting furnace with the opening (9) in the dip furnace. (5) in the metal melt (6). Method according to claim 1, characterized in that at least 80% of the metal oxide film (8) is lifted onto the surface of the metal melt (1) during the passage and remains on the surface of the metal melt (1). Method according to claim 1 or 2, characterized in that the metal oxide film (8) remains in the melt container (2) until the end position is reached. 4. The 1 ~ 3. Method according to one of Claims 1 to 3, characterized in that the metal oxide film (6) has an area opposite to the mold (3) when the end position of the melt container (2) is reached and is spread in the mold (3) on the surface of the metal melt (1). 5. Method according to any one of claims 1 to 3, characterized in that more than 80% of the metal oxide film (δ) is in the end position (3) of the mold (3) in the solidifying position (?) of the mold. 8. A method according to any one of the preceding claims, wherein the metal oxide film (8) remains flexible and intact until the end position is reached. Method according to one of Claims 1 to 8, characterized in that the surface of the metal oxide film (8) in the melt tank (2) increases, while the metal melt (1) is poured from the melt tank (2) into the mold (3). Method according to one of Claims 1 to 7, characterized in that the molten container (2) is connected to the mold (3) prior to pouring and the position of the melt container (2) relative to the mold (3) in the initial position and end position. during the casting. 9. A method according to any one of claims 1 to 3, characterized in that the axis of rotation (a) passes through the mold (3) at the initial position and is either below the cavity (4) or from the melt tank (2> behind the mold cavity (4), or through a cavity (4) or above the cavity. 10. The 1-Θ. A method according to any one of the claims, characterized in that the metal oxide film (8) is placed on or into the pouring opening (7) of the mold (3) after reaching the fin end, the sliding opening (7) sliding in its full width. Method according to claim 10, characterized in that the molten container (2) is moved to the inlet (7) of the mold (3) after immersion of the metal melt (1) from the dipping furnace (3), and the melt tank is discharged. includes a part (8) through which the metal melt is poured into the mold (3) through the pouring opening (?), the contour of the pouring portion {8} in the starting position being vertical from the outline of the bottom section of the pouring opening (7) and the projecting portion (8) is connected directly and concurrently with the filler opening (7), 12. The method of claim 11, wherein the outlet opening (7) has a contour and a projecting portion (8). ) is in a horizontal position or tilted at an angle of up to 30 ° from the horizontal position. Method according to claim 12, characterized in that the contour of the inlet opening (7) and the contour portion (8) of the end position are up to 120ft and at least bCF in the end position. is turned. 14. References 1-13. Method according to any one of the claims, characterized in that the melt container (2) is connected directly to the mold (3) within a time period of not more than 5 seconds after the filling with the metal melt (6) has been completed. 15. Referring to Figures 1-14. Method according to one of Claims 1 to 3, characterized in that the molten container (2) is filled with the metal melt (8) within the immersion furnace (8) for a period of up to 3.5 seconds. 18. The method of Figures 1-15. Method according to one of Claims 1 to 3, characterized in that the melt container (2) and the mold (3) are moved from the initial position to the end position within a maximum of 8 seconds. Method according to any one of claims 1-16, characterized in that the average temperature of the metal melt (6) in the dipping oven (5). it comes from a range of values with a lower limit of 680 t C and a maximum limit of 780 ° C. 18. References 1-17. A method according to any one of claims 1 to 3, characterized in that the bulk container (2) and the mold (3) are transferred from the initial position to the end position under a pressurized atmosphere. 19. References 1-16. Method according to one of Claims 1 to 3, characterized in that at least three molds (10, 11, 12) are used which are arranged in a carousel which carries the three molds (10, 11, 12) from the casting position (I), in which the metal melt (6) is molded. pouring from the container (2) into the mold (10, 11, 12), turning it into the settling position (II), in which the metal melt (1) solidifies in the mold ('10, 11, 12) and then turns into a treatment position (111) in which the mold (10, 11, 12) is opened and the casting is removed from the mold (10, 11, 12) and the mold (10, 11, 12) is cleaned. 20. The method of claim 19, wherein the carousel is further rotated at a constant rate from a value having a lower limit of 70 seconds and an upper limit of 80 seconds.